Thanks deebo
Dr. Aydinmur, yes that is very interesting. Maybe it's because there are simply different things going on between periodontal disease and gingivitis in the way the two situations are able to "communicate" with the inside of the mouth and the microorganisms present there.
The reason I say that is because I still have one remaining wisdom tooth. It's below the gum and horizontally impacted. It never causes me any problems with pain, unless I start to poke around it and go too far.
A few weeks ago I tried to irrigate into the small hole which has formed where the tooth is trying to poke through the flat gum. I did this with warm salty water. The area felt sore and swollen afterwards and I could feel a metallic taste around this entire area. There wasn't any foul discharge detectable with my finger. But the next morning I couldn't believe my eyes, I had a completely white coated tongue. I had a bad taste in my mouth and I went to put my finger onto the back of my tongue and there was a strong fecal/tonsillolith odour, almost as bad as my right lower wisdom tooth was causing until I had it extracted 3 years ago.
I left the tooth alone and it eventually calmed down along with my tongue and the odour.
But it made me wonder whether this minor inflammatory situation around that gum could be all it takes to make bacteria in the mouth behave differently and lead to bad breath?
Could the good correlation between gingivitis and bad breath be purely because of the inflammatory responses that go on with the gums and the direct affect this has on the microorganisms on the tongue, as opposed to the weak correlation between periodontitis and bad breath because the situation isn't able to affect the oral bacteria in the same way?
In some people there may be other inflammatory responses, such as those caused by acid relux, or chronic sinusitus for example, and that this itself releases something which triggers bacterial overactivity on the back of the tongue.
Simply, I just found it so surprising how a slight soreness in my mouth could lead to my tongue turning white and odour to be produced there.